Telephone-transmitter.



G.' P. ATWOOD.

TELEPHONE TRANSMITTER.

APPLICATION FILED MAB.. l2, 1906. 902,043, Patented 013132711908 To allwhom fit may concern:

UNITED srAgis PATENT onirica.

GEORGE 'if ATWOOD, OF lEASTjORAfNGE, NEW JERSEY, ASSIGNOR TO WESTERNELECTRIC l COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

TELEPHONE-TRANSMITTER.

Be it known that LOEORGE F. A'rwooD, citizen of the United States,residing at East Orange, in the county of Essex and State of N ewJersey, haveinvente'd a certain new and useful Improvement inlelephone-Transmitters, of which the following is a, full, clear,

concise, and exact description.

My invention relates to a telephone transmitter, its object being toprovide a transmitter which will be capable of practical outdoor use,and wherein the terminals' are located in posi tion for convenientaccess thereto.

The transmitter of my invention was especially designed for militaryfield use, where it will be subjected ,to hard usage, and be eX.- posedto inclement weather.

One feature of my invention consists in the means which I employ torender the containing case water-tight. 'lhe opening in the frontsupporting plate is covered by a waterproof membrane held in place b themouthpiece of the transmitter, whic preferably comprises a perforateddiskv secured to the front supporting plate over lthe opening therein,said membrane .being secured between said disk and plate. The twomembersvof the case are preferably telescoped and clamped together by aclamping ring which covers the outer joint between said members.

With this arrangement the transmitter is rendered thoroughlywater-tight.

Another feature of my invention consists in the location of theinstrument terminals so that ready access may be had thereto withoutdisturbing the adjustments or connections. To this end I provideafterminal chamber upon the rear of the containing case in which saidterminals are located, the chamber having a removable cap permittingfree access to all the connections of the instrument. The rear wall ofthe containing.,r case has a hole therein opening into the terminalchamber and through which the terminals of .the instrument reject.

When t e transmitter-is used in connection With localv batterytelephones, it is desirable l to have the local battery circuitincluding the transmitter closed'only while the instrument is in use,and a further feature of my invention consists in the switchingmechanism within said chamber and controlled from the outside thereof,for electrically connecting the switch terminals of the transmitter whenthe instrument is desired for u se.

Specification of Letters Patent. Application filed March 12'y 1906.Serial No. 305,549.

Patented Oct. 27, 1908.

I will describe my invention particularly` by reference to theaccompanying drawing wherein I Figure l is a front elevation of atransmitter embodying my invention; Fig. 2 is avertical sectional viewthereof Fi". 3 is a rear view of the front su porting p ate and thetransmitter carried tiereby; Fig, 4 is a rear view of the containingcase of the transmitter and therterminal chamber mounted thereon withthe cap of the chamber removed; and Fig. 5 is a detail sectional viewonline 5-5 of Fig. 3.

Similar letters of reference 'designate like `parts throughout theseveral views. v

The front supporting plate a, carries upon its rear side the Workingparts of the transmitter, said plate having a ce'ntral opening a thereinbefore the diaphragm of the transmitter. A thin ,waterproof membrane o,referably of rubber, covers thelopenin'gr a', liein held in place by themouthpieceI c, whic 1 preferably comprises a perforated disk securedtothe front plate over the opening therein, the membrane being held inAplace between 'the disk and the plate. Moisture is mitter through saidopening.

The front supportingplate cis provided i at its rear with an inclosingmember d, which is preferably cu -shaped, said l arts c d being unitedby a te escopic joint and locked in place by a ring e which seals thejoint. The plate a is rovided with a rearwardly' extend- 4mg annu ar dane c2, which lits within the member d, unti the outwardlyrprojectingannular lug or flange a3 carried by the plate abuts against the edgeofthe m'emberd.

j The clam )ing ring is internally threaded and is adapte to screw uponthe member (l, said ring having an inturned annular ip c adapted toengage said lug a3, thereby locking the parts a d in position andsealing the joint between themto prevent moisture from entering thecase-at such point. j

An auxiliary su port is rovided for the transmitter in the fbrm of aridge piece f sccured at the rear 'of the plate e, upon the inturnedlips a* a4 formed from the annular flange a2. S'

The rear member d of the inclosing cas'e carries on its outer surface achamber o in which are located the terminals of the instrument. 'lhemember (l has an `opening cl therein through which the insulatedterminals oi. -the transmitter carried by the bridge f project into thechamber g, said' terminals being preferably mounted upon an insulatingblock h, secured to said bridge. The iiaiige e2 has a slot c5 thereinwhich is adapted to receive a pin d carried upon theinner surface of themember d to prevent turning of the plate a. Said chamber g also containsthe switch terminals yi i of the transmitter, said terminals beingmounted upon the wall of the chamber but insulated therelro'm. Inpractice one of said switch terminals may be connected with one terminalot the transmitter, the other switch terminal being connected with onepole of the local battery, while the other vtransmitter terminal wouldbe connected with the other pole of the battery, said circuit, ofcourse, including the primary winding et an induction coil.. Thus whenthe switch vterminals are electrically connected, the local circuit ofthe transmitter is completed. v

I provide switching mechanism within the chamber adapted to be operatedfrom the outside thereof for connecting said switch terminals When'thetransmitter is desired for l.use

I 'engaged and connected by a s the adjustmentof the` transmitter.

'Each switch terminal is connected with aaspriug-c, saidv springs beingadapted to be )ring-restored plunger Z pro'ecting through t e Wall ofthe chamber. T e terminals are thus located in position for ready accesswithout disturbing A removab e capI m is provided for the chamberpermitting access .cto said chamber. Conductors may be led to saidterminals through a tube n' communicating with an opening in the wall ofthe chainiier.

l 1. The combination With a telephone transmitter, of a containing casetherefor, a chamber secured to the rear wallet the case, said Wallhaving .a hole therein opening into said chamber, and an insulated'block carrying the transmitter terminals projecting through saidopeninginto said chamber.

2. The combination with a telephone transmitter, of va front supportingplate for supporting the Working parts of the transvmitter,.an auxiliarysupport for the transmitter carried by the plate behind the transmitter,insulated terminals for the transmit- `ter carried by said support, Iacup-shaped member secured to the rear of said'plate, a

chamber upon the outer surface of said member, and a removable cap forsaid chamber, -the terminals carried by said support projectingthroughan o ening in saidcupshaped member into sai chamber y 3.The 'combinationwith a telephone transmitter, of a front supporting plate having arearwardly extending flange, a bridge piece lat the rear 'of thetransmitter, inwardly projecting lips formed from said flange andsupporting said bridge piece, an insulated block mounted upon. saidbridge piece and carrying the transmitter terminals, a cupshaped. memberwithin which the flange of the front plate iits, nieans'for securingsaid plate and member together to form an in-` closing casing for thetransmitter, and a terminal chamber mounted upon the rear ofsaidcup-shaped member, saidy member having an opening therein through whichsaid block projects into said chamber.

4. A containing case for telephone transmitters comprising a l'rontsupporting plate having4 a rearwardlyextending` annular flange, acup-shaped member in which said flange iits, an outwardly rejectingannular lug carried by said plate a utting against the. edge of saidcup-shaped member, said member having screw threads upon its outersurface, an -internally threaded clamping ringv screwing upon saidcup-shaped member, and an inturned annular lip'cariied by said ring andabutting against said outwardly projecting lug, whereby said cup-shapedmember an'd iront plate are locked together and the joint between saidparts sealed.

5. The combination with a telephone transmitter, of a containing casetherefor, a

chamber secured to the rear Wall of the case,

said wall having a hole therein opening into said chamber, an insulatedblock mounted within said containing case, transmitter terminals mountedon said block and projecting through said opening into said chamber, anda spring-pressed plunger passing through the side walls of said chamberand arranged to control the connection of said switch ter'ininals. I

6. The combination with a telephone transmitter, ol *a containing casetherefor, a chamber secured to the rear wall ofthe case,

vsaid wall having a hole thereinopcning into said chamber, an. insulatedblock mounted within said case, transmitter terminals mounted on saidblock yand projecting through said opening into said chamber, a pair oisprings connected with said terminals, and a plunger passing through theWall of said chamberv and arranged when operated to connect said'springs.

l In witness whereof, l, hereuntosubscribe my name this 3rd day ot'MarchA. D., 1906.

WM. B. Toti, R. EDWARDS, Jr. v

